Hydraulic brake impulse regulator for trailers



April I, 1941. J. R. WATSON HYDRAULIC BRAKE IMPULSE REGULATOR FOR TRAILERS Filed Dec. 6, 1959 2 Sheets-Sheet 1 Inventor James E n azsow Attorneys April 1, 1941. J. R. WATSON HYDRAULIC BRAKE IMPULSE REGULATOR FOR TRAILERS 2 Sheets-Sheet 2 Filed Dec. 6, 1939 Attorneys Patented Apr. 1, 1941 BRAKE IBIPULSE REGULATOR FOR TRAILERS I HYDRAULIC F-FICE James R. Watson, San Bernardino, Calif. Application December 6, 1939, Serial No. 307,918

4 Claims.

The present invention relates to hydraulic brake impulse regulators which are operated in a train and has for its primary object to provide means whereby the braking impulse or portionsthereof may be regulated or selectively retarded for applying the brakes of the respective vehicles of the train, or at the option of the driver or operator he may so direct the brake impulse toward that portion of the train that requires, by virtue of the load carried, the greatest amount of braking and if he so desires by selectivity to promote a pressure constant at said selected point. By so doing a preferred embodiment of the invention, the numeral 5 designates a tractor connected with a front trailer 6 and to the rear end of which is secured a rear trailer 1.

the heavier braking force may be applied where the greatest load is carried and minimizes tire wear on light loaded portions where braking is not needed.

In those instances where conditions are found in heavy duty hauling or various and sundry other conditions, when a tractor or truck may be hitched to one or more trailers it is desirable to provide a braking system where the braking impulse first takes effect at the rear of the entire hook-up and travels forwardly, finally equalizing throughout the entire unit.

It is accordingly an object of the present in vention to provide control means in the system and operable from a point in the tractor to selectively regulate the braking impulse trans-- mitted to the various vehicles.

A further object is to provide a device of this character of simple and practical-construction, which is efficient and reliablev in performance, relatively inexpensive to install in operative position and otherwise well adapted for the purposes for which the same is intended. a

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described. and claimed, reference being had to the accompanying, drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which Figure l is a top plan view of a vehicle train showing the braking system provided therefor.

Figure 2 is a front elevational view of the housing for the control valve in the system for the various brakes.

Figure 3 is a sectional view taken through one of the control units substantially on a line 3--3 of Figure 2.

Figure 4 is a sectional view taken substantially on a line 4-4 of Figure 3, and

Figure 5 is a top plan view of the cage for one of the check valves.

Referring now to the drawings in detail, wherein for the purpose of illustration I have disclosed The master cylinder of the hydraulic brake system is designated at 8 which is operated by the brake pedal (not shown) in the usual manner from-the tractor 5 and to which is connected the pipe 9 leading to the housing ll) of a pressure regulating unit in which a main chamber II is provided having direct communication with the pipe 9.

, I The housing I0 is preferably of substantially triangular shape in cross section, as more clearly shown in Figure 3 of the drawings, and is provided with a top cover plate l2 positioned at an inclined angle with respect to the driver of the tractor to constitute a control panel. Arranged in the housing beneath the main chamber II are a plurality of control chambers l3 separated from each other by partitions I4 and having com-- munication with the main chamber by means of a nipple l5 having its end adjacent the main chamber provided with a valve seat IS. A valve I! is threaded through a packing member I 8 with its inner end adapted to seat on the valve seat l6 and having its outer end provided with the manipulating knob l9.

Communicating with one of the control chambers I3 is a pipe 20 leading to the'brakes 2| of the tractor, while a pipe 22 leads from another of the control chambers l3 to the brakes 23 of the front trailer Band a pipe 24 leads from still another of the control chambers [3 to the brakes 25 of the rear trailer 7. Each of the control chambers I3 is, of course, provided with one of the control valves".

Avpressure release passage 26 is also provided between each of the control chambers l3 and the main chamber l l and is controlled by a ball check valveZl mounted in a cage 28 removably secured in, position over the ball. The top of the cage is formed with an opening 29 0f irregularcontour to prevent restriction of the return of the fluid from the control chamber l 3 into the main chambraking pressure of one hundred and fifty pounds per square inch, the tractor 5,.weighs two and a half tons, the trailer 6 plus load weighs five tons and the trailer 1 plus load weighs ten tons. All reduction valves 30 are opened, preferably, .by hand wheels 3| in which position of these valves the pressure gauges 32 read zero. Trailer I being the heaviest unit of the train and also therear one, should receive the maximum braking pressure undelayed and first. Therefore, the operator sets valve l1 related to line 24 of the rear trailer to open position. The trailer 6 weighing fifty per cent less than trailer I should receive fifty per cent less braking pressure delayed. Therefore valve ll related to line 22 of trailer 6 is open half way. Tractor} should receive fifty per cent less braking pressure than trailer G further delayed. Therefore, valve ll related to line 20 of tractor 5 is opened one quarter. Under suchsettings of valves l1, trailer 1, trailer 6 and tractor 5 receive one hundred and fifty pounds, seventy-fiveandthirty-sevenand one-half pounds pressure, respectively, and successively beginning with the rear trailer 1. After the brakes have been applied and taken effect the braking pressure against all units is gradually equalized as obviously the system will eventually equalize itself.

Considering now a different situation, as for instance, braking for a 15 mile down grade, where constant braking is desired and it is preferable that pressure predetermined by setting of the valves H, for instance those pressures'previously discussed, be maintained so as to apply the same for a long period of time. Valves; 11 are opened to the same extent as previously indicated to apply one. hundred and fifty pounds, seventy-five the main chamber H into the respective control ing from each control chamber to the brakes of the respective vehicles and a check valve between 7 each control chamber and the main chamber pounds and thirty-seven and one-half pounds pressure to the trailer 1, trailer 6 and tractor 5, respectively just as in the first discussed situation. Then the reduction valves 30 related to lines 20, 22 and 24 of tractor 5, trailer 6 and trailer 1, respectively, are closed to set the same at thirty-seven and one-half pounds, seventy five pounds and one hundred and fifty pounds respectively. Thus the predetermined pressures are maintained in the lines 20, 22, 24 for the required period of time, the reduction valves 30 operating as governors maintaining the flow of pressures predetermined by valves ll constant.

It is believed the details of construction and manner of operation of thedevicewill be readily adapted to accelerate return of fluid from the control chambers to the main chamber.

2. A control device for the hydraulic brake system of a vehicle train wherein each vehicle of the trainis provided with individual brakes, said control device comprising a housing having a cover plate, a main chamber in the housing communicating with a master brake cylinder, a plurality of individual chambers in the housing communicating with the brakes of the respective vehicles, a passage between each control chamber and the main chamber, a manually operable valve for each passage and carried by the cover plate and a check valve between each control chamber andthe main chamber arranged to open upon a release of the brakes.

3. In a hydraulic brake system for a Vehicle train in which each vehicle is provided with individual brakes operated through a master brake cylinder and control means between the master cylinder and the brakes adapted to proportion the brakimg impulse transmitted to the respective brakes, said control means comprising a chamber common to all of the' brakes and having a fluid conduit connected to the master. cylinder, feed pipes for the respective brakes and valves controlling passage of the fluid from the chamber to the feed pipes. 4

4. A control device for the hydraulic brake system of a vehicle train wherein each vehicle of the train is provided with individual brakes, said control device comprising a housing having a main chamber therein, a conduit leading from a source of fluid brakingforce to the chamber, a plurality of control chambers in the housing. each having communication with the main chamber, a manual control valve between each control chamber and the main chamber, conduits leading from each control chamber to the brakes of the respective vehicles, a check valve between each control chamber and themain chamber adapted to accelerate return of fluid from the control chambers to the main chamber and a manually controlled valve between each control chamber and its connected brake.

JAMES R. WATSON. 

